Leaf-footed bugs are members of the Squash Bug and Leaf-footed Bug Family (Coreidae). Leaf-footed bugs can be recognized by the large, flattened areas shaped like leaves on the tibiae of their hind legs.
I observed this leaf-footed bug feeding on the flowers of a Banana Yucca (Yucca baccata) here in August. I don't know the species of leaf-footed bug, but it is likely in the genus Leptoglossus. Leaf-footed bugs feed on plants and some of them are serious plant pests.
Leaf-footed bugs will use their long, piercing mouthparts to puncture plants and then inject some of their saliva into the pierced areas to partly digest and dissolve the plant tissues. The leaf-footed bug will then suck up the partly digested mixture. Areas of the plant damaged by leaf-footed bugs will no longer grow, stunting the plant or causing it or its fruit to be weirdly deformed. Not only does their feeding weaken and damage plants, it can also spread serious plant diseases.